It is well-known that a cyclic olefin random copolymer obtained by copolymerimerization of ethylene with a cyclic olefin, a ring-opening polymer of a cyclic olefin, and a hydrogenated product thereof are synthetic resins that provide excellent transparency while also striking a good balance between in low birefringence, heat resistance, heat aging resistance, chemical resistance, solvent resistance, and rigidity, and they are known to exhibit excellent performances in the field of optical materials such as optical memory disks and optical fibers.
Patent Document 1 discloses a cyclic olefin polymer composition that provides excellent in transparency, low birefringence, heat resistance, heat aging resistance, chemical resistance, solvent resistance, and the like, and in particular, can stably maintain excellent transparency even if the environment changes.
[Patent Document 1] JP-A-H09-176397